include/wx/unichar.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/unichar.h
   3 // Purpose:     wxUniChar and wxUniCharRef classes
   4 // Author:      Vaclav Slavik
   5 // Created:     2007-03-19
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2007 REA Elektronik GmbH
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_UNICHAR_H_
  12 #define _WX_UNICHAR_H_
  13
  14 #include "wx/defs.h"
  15 #include "wx/chartype.h"
  16
  17 class WXDLLIMPEXP_BASE wxUniCharRef;
  18
  19 // This class represents single Unicode character. It can be converted to
  20 // and from char or wchar_t and implements commonly used character operations.
  21 class WXDLLIMPEXP_BASE wxUniChar
  22 {
  23 public:
  24     // NB: this is not wchar_t on purpose, it needs to represent the entire
  25     //     Unicode code points range and wchar_t may be too small for that
  26     //     (e.g. on Win32 where wchar_t* is encoded in UTF-16)
  27     typedef wxUint32 value_type;
  28
  29     wxUniChar() : m_value(0) {}
  30
  31     // Create the character from 8bit character value encoded in the current
  32     // locale's charset.
  33     wxUniChar(char c) { m_value = From8bit(c); }
  34     wxUniChar(unsigned char c) { m_value = From8bit((char)c); }
  35
  36     // Create the character from a wchar_t character value.
  37     wxUniChar(wchar_t c) { m_value = c; }
  38
  39 #ifndef wxWINT_T_IS_TYPEDEF
  40     // Create the character from a wint_t character value.
  41     wxUniChar(wint_t c) { m_value = c; }
  42 #endif
  43
  44     wxUniChar(int c) { m_value = c; }
  45
  46     wxUniChar(const wxUniCharRef& c);
  47
  48     // Returns Unicode code point value of the character
  49     value_type GetValue() const { return m_value; }
  50
  51     // Casts to char and wchar_t types:
  52     operator char() const { return To8bit(m_value); }
  53     operator unsigned char() const { return (unsigned char)To8bit(m_value); }
  54     operator wchar_t() const { return m_value; }
  55 #ifndef wxWINT_T_IS_TYPEDEF
  56     operator wint_t() const { return m_value; }
  57 #endif
  58     operator int() const { return m_value; }
  59     operator unsigned int() const { return m_value; }
  60
  61     // We need this operator for the "*p" part of expressions like "for (
  62     // const_iterator p = begin() + nStart; *p; ++p )". In this case,
  63     // compilation would fail without it because the conversion to bool would
  64     // be ambiguous (there are all these int types conversions...). (And adding
  65     // operator unspecified_bool_type() would only makes the ambiguity worse.)
  66     operator bool() const { return m_value != 0; }
  67     bool operator!() const { return !((bool)*this); }
  68 #if (defined(__VISUALC__) && __VISUALC__ < 1400) || \
  69     defined(__DIGITALMARS__) || defined(__BORLANDC__)
  70     // We need this for VC++ < 8 or DigitalMars and expressions like
  71     // "str[0] && *p":
  72     bool operator&&(bool v) const { return (bool)*this && v; }
  73 #endif
  74
  75     // Assignment operators:
  76     wxUniChar& operator=(const wxUniChar& c) { m_value = c.m_value; return *this; }
  77     wxUniChar& operator=(char c) { m_value = From8bit(c); return *this; }
  78     wxUniChar& operator=(wchar_t c) { m_value = c; return *this; }
  79 #ifndef wxWINT_T_IS_TYPEDEF
  80     wxUniChar& operator=(wint_t c) { m_value = c; return *this; }
  81 #endif
  82
  83     // Comparison operators:
  84
  85     // define the given comparison operator for all the types
  86 #define wxDEFINE_UNICHAR_OPERATOR_NO_WINT(op)                                 \
  87     bool operator op(const wxUniChar& c) const { return m_value op c.m_value; }\
  88     bool operator op(char c) const { return m_value op From8bit(c); }         \
  89     bool operator op(wchar_t c) const { return m_value op (value_type)c; }
  90
  91 #ifdef wxWINT_T_IS_TYPEDEF
  92     #define wxDEFINE_UNICHAR_OPERATOR wxDEFINE_UNICHAR_OPERATOR_NO_WINT
  93 #else // wint_t is a separate type, need to overload for it too
  94     #define wxDEFINE_UNICHAR_OPERATOR(op)                                     \
  95         wxDEFINE_UNICHAR_OPERATOR_NO_WINT(op)                                 \
  96         bool operator op(wint_t c) const { return m_value op (value_type)c; }
  97 #endif
  98
  99     wxFOR_ALL_COMPARISONS(wxDEFINE_UNICHAR_OPERATOR)
 100
 101 #undef wxDEFINE_UNICHAR_OPERATOR_NO_WINT
 102 #undef wxDEFINE_UNICHAR_OPERATOR
 103
 104     // this is needed for expressions like 'Z'-c
 105     int operator-(const wxUniChar& c) const { return m_value - c.m_value; }
 106     int operator-(char c) const { return m_value - From8bit(c); }
 107     int operator-(wchar_t c) const { return m_value - (value_type)c; }
 108 #ifndef wxWINT_T_IS_TYPEDEF
 109     int operator-(wint_t c) const { return m_value - (value_type)c; }
 110 #endif
 111
 112 private:
 113     static value_type From8bit(char c);
 114     static char To8bit(value_type c);
 115
 116 private:
 117     value_type m_value;
 118 };
 119
 120
 121 // Writeable reference to a character in wxString.
 122 //
 123 // This class can be used in the same way wxChar is used, except that changing
 124 // its value updates the underlying string object.
 125 class WXDLLIMPEXP_BASE wxUniCharRef
 126 {
 127 private:
 128     // create the reference
 129     // FIXME-UTF8: the interface will need changes for UTF-8 build
 130     wxUniCharRef(wxChar *pos) : m_pos(pos) {}
 131
 132 public:
 133     // NB: we have to make this public, because we don't have wxString
 134     //     declaration available here and so can't declare wxString::iterator
 135     //     as friend; so at least don't use a ctor but a static function
 136     //     that must be used explicitly (this is more than using 'explicit'
 137     //     keyword on ctor!):
 138     //
 139     // FIXME-UTF8: the interface will need changes for UTF-8 build
 140     static wxUniCharRef CreateForString(wxChar *pos)
 141         { return wxUniCharRef(pos); }
 142
 143     wxUniChar::value_type GetValue() const { return UniChar().GetValue(); }
 144
 145     // Assignment operators:
 146     wxUniCharRef& operator=(const wxUniCharRef& c)
 147     {
 148         *m_pos = *c.m_pos;
 149         return *this;
 150     };
 151
 152     wxUniCharRef& operator=(const wxUniChar& c)
 153     {
 154         *m_pos = c;
 155         return *this;
 156     };
 157
 158     wxUniCharRef& operator=(char c) { return *this = wxUniChar(c); }
 159     wxUniCharRef& operator=(wchar_t c) { return *this = wxUniChar(c); }
 160
 161     // Casts to wxUniChar type:
 162     operator char() const { return UniChar(); }
 163     operator unsigned char() const { return UniChar(); }
 164     operator wchar_t() const { return UniChar(); }
 165 #ifndef wxWINT_T_IS_TYPEDEF
 166     operator wint_t() const { return UniChar(); }
 167 #endif
 168     operator int() const { return UniChar(); }
 169     operator unsigned int() const { return UniChar(); }
 170
 171     // see wxUniChar::operator bool etc. for explanation
 172     operator bool() const { return (bool)UniChar(); }
 173     bool operator!() const { return !UniChar(); }
 174 #if (defined(__VISUALC__) && __VISUALC__ < 1400) || \
 175     defined(__DIGITALMARS__) || defined(__BORLANDC__)
 176     bool operator&&(bool v) const { return UniChar() && v; }
 177 #endif
 178
 179     // Comparison operators:
 180 #define wxDEFINE_UNICHARREF_OPERATOR_NO_WINT(op)                              \
 181     bool operator op(const wxUniCharRef& c) const { return UniChar() op c.UniChar(); }\
 182     bool operator op(const wxUniChar& c) const { return UniChar() op c; }     \
 183     bool operator op(char c) const { return UniChar() op c; }                 \
 184     bool operator op(wchar_t c) const { return UniChar() op c; }
 185
 186 #ifdef wxWINT_T_IS_TYPEDEF
 187     #define wxDEFINE_UNICHARREF_OPERATOR wxDEFINE_UNICHARREF_OPERATOR_NO_WINT
 188 #else // wint_t is a separate type, need to overload for it too
 189     #define wxDEFINE_UNICHARREF_OPERATOR(op)                                  \
 190         wxDEFINE_UNICHARREF_OPERATOR_NO_WINT(op)                              \
 191         bool operator op(wint_t c) const { return UniChar() op c; }
 192 #endif
 193
 194     wxFOR_ALL_COMPARISONS(wxDEFINE_UNICHARREF_OPERATOR)
 195
 196 #undef wxDEFINE_UNICHARREF_OPERATOR_NO_WINT
 197 #undef wxDEFINE_UNICHARREF_OPERATOR
 198
 199     // for expressions like c-'A':
 200     int operator-(const wxUniCharRef& c) const { return UniChar() - c.UniChar(); }
 201     int operator-(const wxUniChar& c) const { return UniChar() - c; }
 202     int operator-(char c) const { return UniChar() - c; }
 203     int operator-(wchar_t c) const { return UniChar() - c; }
 204 #ifndef wxWINT_T_IS_TYPEDEF
 205     int operator-(wint_t c) const { return UniChar() - c; }
 206 #endif
 207
 208 private:
 209     wxUniChar UniChar() const { return *m_pos; }
 210     friend class WXDLLIMPEXP_BASE wxUniChar;
 211
 212 private:
 213     // pointer to the character in string
 214     wxChar *m_pos;
 215 };
 216
 217 inline wxUniChar::wxUniChar(const wxUniCharRef& c)
 218 {
 219     m_value = c.UniChar().m_value;
 220 }
 221
 222 // Comparison operators for the case when wxUniChar(Ref) is the second operand
 223 // implemented in terms of member comparison functions
 224
 225 #define wxCMP_REVERSE(c1, c2, op) c2 op c1
 226
 227 wxDEFINE_COMPARISONS(char, const wxUniChar&, wxCMP_REVERSE)
 228 wxDEFINE_COMPARISONS(char, const wxUniCharRef&, wxCMP_REVERSE)
 229
 230 wxDEFINE_COMPARISONS(wchar_t, const wxUniChar&, wxCMP_REVERSE)
 231 wxDEFINE_COMPARISONS(wchar_t, const wxUniCharRef&, wxCMP_REVERSE)
 232
 233 #ifndef wxWINT_T_IS_TYPEDEF
 234 wxDEFINE_COMPARISONS(wint_t, const wxUniChar&, wxCMP_REVERSE)
 235 wxDEFINE_COMPARISONS(wint_t, const wxUniCharRef&, wxCMP_REVERSE)
 236 #endif
 237
 238 wxDEFINE_COMPARISONS(const wxUniChar&, const wxUniCharRef&, wxCMP_REVERSE)
 239
 240 #undef wxCMP_REVERSE
 241
 242 // for expressions like c-'A':
 243 inline int operator-(char c1, const wxUniCharRef& c2) { return -(c2 - c1); }
 244 inline int operator-(wchar_t c1, const wxUniCharRef& c2) { return -(c2 - c1); }
 245 #ifndef wxWINT_T_IS_TYPEDEF
 246 inline int operator-(wint_t c1, const wxUniCharRef& c2) { return -(c2 - c1); }
 247 #endif
 248 inline int operator-(const wxUniChar& c1, const wxUniCharRef& c2) { return -(c2 - c1); }
 249
 250 #endif /* _WX_UNICHAR_H_ */